Switchable Plasmonic–Dielectric Resonators with Metal–Insulator Transitions

5 years ago

Switchable Plasmonic–Dielectric Resonators with Metal–Insulator Transitions

Jon A. Schuller, Ivan K. Schuller, Stephen D. Wilson, Christian Urban, Alexander A. Mikhailovsky, Zhensong Ren, Nikita A. Butakov, Tomer Lewi, Ilya Valmianski

Nanophotonic resonators offer the ability to design nanoscale optical elements and engineered materials with unconventional properties. Dielectric-based resonators intrinsically support a complete multipolar resonant response with low absorption, while metallic resonators provide extreme light confinement and enhanced photon–electron interactions. Here, we construct resonators out of a prototypical metal–insulator transition material, vanadium dioxide (VO₂), and demonstrate switching between dielectric and plasmonic resonances. We first characterize the temperature-dependent infrared optical constants of VO₂ single crystals and thin-films. We then fabricate VO₂ wire arrays and disk arrays. We show that wire resonators support dielectric resonances at low temperatures, a damped scattering response at intermediate temperatures, and plasmonic resonances at high temperatures. In disk resonators, however, upon heating, there is a pronounced enhancement of scattering at intermediate temperatures and a substantial narrowing of the phase transition. These findings may lead to the design of novel nanophotonic devices that incorporate thermally switchable plasmonic–dielectric behavior.

Publisher URL: http://dx.doi.org/10.1021/acsphotonics.7b00334

DOI: 10.1021/acsphotonics.7b00334